1. Field of the Invention
This invention relates, generally, to an apparatus for melting snow and ice. More particularly, it relates to a removable device for preventing the accumulation of snow and ice on walkways and driveways by heating means.
2. Description of the Related Art
Heating elements have been used in the past to warm walkways and driving surfaces to prevent the accumulation of snow and ice. For example, U.S. Pat. Nos. 2,231,251, 2,844,696, 2,912,555, 3,047,701, 3,418,448, 3,812,320, 4,646,818, 4,967,057, 5,003,157, 5,380,988 and 5,591,365 disclose various devices useful in preventing the accumulation of snow and ice on walkways and driving surfaces. In general, these devices are relatively portable and are storable when not in use. U.S. Pat. No. 5,395,179 discloses a device which is a more permanent structure which can be flush with the ground surface to reduce the possibility of breakage of the inside heat generating elements.
However, all of these prior art devices have various shortcomings. For example, devices such as those disclosed in U.S. Pat. Nos. 5,591,365, 5,003,157 and 2,231,251 require the use of large quantities of electrical energy to heat and maintain a temperature sufficient to melt a relatively small surface area of ice and snow. The device disclosed U.S. Pat. No. 2,844,696 discloses a design which is impractical for exterior use and poses safety concerns including a potential shock hazard and short circuiting of the device, if it becomes submerged in melted snow and ice.
In addition, the device disclosed in U.S. Pat. No. 4,646,818, which is made up of individual tubes, is impractical for vehicular traffic. If enough weight is placed on one or more of the individual tubes, fluid flow is greatly diminished, if not completely blocked from a particular section of the device which allows the accumulation of ice and snow on the affected section. Further, the devices disclosed in U.S. Pat. Nos. 2,912,555, 3,418,448 and 5,380,988 are made up of rigid panels which restrict their usefulness to flat even surfaces and make movement and storage difficult.
Thus, what is needed then is an apparatus for melting and preventing the accumulation of snow and ice on walkways and driveways which is energy efficient, easily removable, storable when not in use and overcomes the problems associated with tube failure due to the weight of vehicular traffic or otherwise.
In view of the prior art as a whole at the time the present invention was made, it was not obvious to those of ordinary skill in the pertinent art how the apparatus could be provided.